Surface modification of polyamide nanofiber membranes by polyurethane to simultaneously improve their mechanical strength and hydrophobicity for breathable and waterproof applications
作者：Wen Yang, Ran Li, Caiping Fang, Wentao Hao
關鍵字：Electrospun, Nanofiber membrane, Robust, Waterproof, Breathable
論文來源：期刊
具體來源：https://doi.org/10.1016/j.porgcoat.2019.02.012
發表時間：2019年
In this work, a simple method was proposed to fabricate robust, breathable and waterproof polymer nanofiber membranes. In a typical process, polyamide-6 (PA-6) electrospun membranes were immersed into polyurethane (PU)/DMF solutions for 24 h, and then taken out and dried. SEM results showed that PA-6 nanofibers in the membranes adhered to each other at the inter-fiber junction points. Moreover, the nanofibers were covered by a thin layer of PU, which was also proved by FTIR results. The DSC and WAXD results suggested that the PU had interacted with the PA-6 at molecular level. Through adhesion bonding, the PA-6 nanofiber membrane was interlinked into a huge network, leading to drastically increment in tensile strength of these membranes (357% that of the original value). Moreover, the PA-6 membranes achieved good waterproof ability after the PU solution treatment. The water contact angle was 135.8°, comparable to that of the poly(vinylidene fluoride) (PVDF) electrospun membrane or fluorinated PU/PU coelectrospun membrane. Interestingly, the PU solution treated PA-6 membranes preserved good breathability. It is a facile and scalable approach to fabricate the robust, breathable and waterproof polymer nanofiber membranes.